\documentclass{ctexbeamer}
\usetheme[min]{sjtubeamer}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\begin{document}
\begin{frame}
  \frametitle{统计图}
  \begin{figure}
    \begin{tikzpicture}
      \begin{axis}[
          xlabel={$n$}, ylabel={Average Steps}, ymin={0}, xmax={9},
          xmin={1}, legend style={at={(0.5,1.05)}, anchor=south},
          legend columns=2, grid, minor tick num=1]
        \pgfplotstableread
        {test.csv}{\foo};
        \addplot+ [only marks, mark options={scale=0.8}] table [y=Quick] {\foo};
        \addplot+ [only marks, mark options={scale=0.8}] table [y=Cocktail]
          {\foo};
        \pgfplotsset{cycle list shift=-2};
        \addplot+ [no markers, domain=1:9,] {1.502*x*ln(x)};
        \addplot+ [no markers, domain=1:9,] {0.4453*x*x-0.1365*x-0.473};
        \legend{Quick,Cocktail}
      \end{axis}
    \end{tikzpicture}
    \caption{统计图标题}
  \end{figure}
\end{frame}
\end{document}